People around the world are becoming more concerned about the climate and environmental impact of their food choices. Readers of this website will be aware of the carbon footprint of what we put on our plates but it’s just as important to shrink the water footprint of our food.
A new report shows how the climate crisis and global heating are making current water shortages significantly worse and that if we don’t carefully manage water scarcity, there will be a significant risk to our food security. The report by the authoritative World Resources Institute www.wri.org spells out the scope of the challenge but also offers ways that we as individuals can be part of the solution.
The Challenge
The world needs at least 60% more food to feed nearly 10 billion people by 2050 and the production of much of that food has a voracious thirst for water. Even more challenging, much of the global food supply is grown in water-stressed regions of the world. The WRI report states that humans use twice as much water today as we did in 1960, and that 70% of the water used globally goes to produce food — mainly for crop irrigation and feeding livestock.
“Climate change makes satisfying this growing thirst more complicated as rainfall patterns shift and hotter temperatures necessitate more water use due to faster evaporation,” WRI says.
Water withdrawal is the total amount of water withdrawn from surface or groundwater sources. In contrast, water consumption is the portion of withdrawn water permanently lost from its source. Consumption means that water is no longer available due to factors such as evaporation, transpiration or use by plants, and consumption by livestock or people.
Almost 75% of global crops are rainfed while the remainder are irrigated. WRI says that rainfed crops are more vulnerable to water scarcity and global heating, and that changing climate patterns are making crop production more unpredictable. For example, farmers in North America have seen spring flooding threaten seeding while rain or snowfall is impeding harvesting, and crops may not have received sufficient rainfall during the growing season. And food production for millions of people in sub-Saharan Africa is being undermined by increased drought and shorter growing seasons, exacerbated by the climate crisis.
One-quarter of all cropland is irrigated and produces 40% of all global food supplies. The WRI report says that one-third of irrigated crops are subject to “extremely high water stress” and that the current rate of water withdrawals is highly unsustainable.
Global food supplies rely on four major crops: wheat, corn, rice and soy. Wheat is subject to the highest demand for household consumption and faces the highest threat from water shortages. WRI says that more than half of global wheat production currently faces “extremely high water stress” and 75% of wheat production will be under threat by 2040.
“Wheat is crucial for food security and economies in every corner of the world.”
Solutions
WRI recommends two major ways that we can all shrink the water footprint of our food choices.
First, by shifting to less water-intensive foods. As the chart shows, plant based foods have a much lower water use than meat and dairy. For example, the water footprint of potatoes is 50 times lower than that of beef.
Secondly, by reducing food loss and waste. “One quarter of all water used for agriculture grows food that is ultimately wasted.” So, cutting food loss and waste is cutting water waste. WRI also recommends that farmers should receive government subsidies to harvest rainwater and reduce water use with efficient drip irrigation systems.
WRI says that climate change heightens water scarcity and, “if water is not managed more sustainably, thirsty cropland will become a barrier to food security.” As individuals, we can make a difference by eating less water by putting less thirsty food on our plates.